Android 软件自动更新功能的实现

1、一个好的应用软件都是需要好的维护，从初出版本到最后精品，这个过程需要版本不停的更新，那么如何让用户第一时间获取最新的应用安装包呢？那么就要求我们从第一个版本就要实现升级模块这一功能。自 动更新功能的实现原理，就是我们事先和后台协商好一个接口，我们在应用的主Activity里，去访问这个接口，如果需要更新，后台会返回一些数据(比 如，提示语；最新版本的url等)。然后我们给出提示框，用户点击开始下载，下载完成开始覆盖安装程序，这样用户的应用就保持最新的拉。为了让大家容易理解，我像往常一样准备一个小例子，这里为了方便我就省去了和后台交互部分了。步骤分别如下：第一步：新建一个Android工程命名为

2、:UpdateDemo.代码结构如下图所示：第二步：新建一个UpdateManager.java类，负责软件更新功能模块，代码如下：?12345678910111213141516171819202122232425262728293031323334353637383940414243444546474849505152535455565758596061626364656667686970717273747576777879808182838485868788899091929394959697989910010110210310410510610710810911011111211311

3、4115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198package com.tutor.update; import java.io.F

4、ile;import java.io.FileOutputStream;import java.io.IOException;import java.io.InputStream;import .HttpURLConnection;import .MalformedURLException;import .URL;  import android.app.AlertDialog;import android.app.Dialog;import android.app.AlertDialog.Builder;import android.content.Context;imp

5、ort android.content.DialogInterface;import android.content.Intent;import android.content.DialogInterface.OnClickListener;import .Uri;import android.os.Handler;import android.os.Message;import android.view.LayoutInflater;import android.view.View;import android.widget.ProgressBar; public class Up

6、dateManager      private Context mContext;         /提示语    private String updateMsg = "有最新的软件包哦，亲快下载吧"         /返回的安装包url    priva

7、te String apkUrl = ":8080/msoft/179/24659/43549/qq_hd_mini_1.4.apk"              private Dialog noticeDialog;         private Dialog downloadDialog;   

8、0; /* 下载包安装路径 */    private static final String savePath = "/sdcard/updatedemo/"         private static final String saveFileName = savePath + "UpdateDemoRelease.apk"     /* 进度条与通知ui刷新的

9、handler和msg常量 */    private ProgressBar mProgress;          private static final int DOWN_UPDATE = 1;         private static final int DOWN_OVER = 2;      

10、   private int progress;         private Thread downLoadThread;         private boolean interceptFlag = false;         private Handler mHandler = new

11、Handler()        public void handleMessage(Message msg)             switch (msg.what)             case DOWN_UPDATE:    &

12、#160;           mProgress.setProgress(progress);                break;            case DOWN_OVER: &#

13、160;                               installApk();                b

14、reak;            default:                break;                   

15、;              public UpdateManager(Context context)         this.mContext = context;             /外部接口让主Activity调用 

16、0;  public void checkUpdateInfo()        showNoticeDialog();                  private void showNoticeDialog()        Ale

17、rtDialog.Builder builder = new Builder(mContext);        builder.setTitle("软件版本更新");        builder.setMessage(updateMsg);        builder.setPositiveButton("下载"

18、, new OnClickListener()                     Override            public void onClick(DialogInterface dialog, int which)    

19、60;            dialog.dismiss();                showDownloadDialog();               &

20、#160;              );        builder.setNegativeButton("以后再说", new OnClickListener()                 

21、;      Override            public void onClick(DialogInterface dialog, int which)                 dialog.dismiss();  

22、60;                               );        noticeDialog = builder.create();     

23、;   noticeDialog.show();             private void showDownloadDialog()        AlertDialog.Builder builder = new Builder(mContext);        bu

24、ilder.setTitle("软件版本更新");                 final LayoutInflater inflater = LayoutInflater.from(mContext);        View v = inflater.inflate(R.gress, null);&#

25、160;       mProgress = (ProgressBar)v.findViewById(R.gress);                 builder.setView(v);        builder.setNegativeButton(&quo

26、t;取消", new OnClickListener()             Override            public void onClick(DialogInterface dialog, int which)           

27、;      dialog.dismiss();                interceptFlag = true;                    ); &

28、#160;      downloadDialog = builder.create();        downloadDialog.show();                 downloadApk();      

29、60;      private Runnable mdownApkRunnable = new Runnable()            Override        public void run()            

30、0;try                 URL url = new URL(apkUrl);                            

31、0;HttpURLConnection conn = (HttpURLConnection)url.openConnection();                conn.connect();                int length = conn.getConte

32、ntLength();                InputStream is = conn.getInputStream();                         

33、0;       File file = new File(savePath);                if(!file.exists()                  

34、0; file.mkdir();                                String apkFile = saveFileName;         

35、60;      File ApkFile = new File(apkFile);                FileOutputStream fos = new FileOutputStream(ApkFile);             &

36、#160;                   int count = 0;                byte buf = new byte1024;        

37、;                         do                        

38、60;           int numread = is.read(buf);                    count += numread;           &

39、#160;        progress =(int)(float)count / length) * 100);                    /更新进度             

40、;       mHandler.sendEmptyMessage(DOWN_UPDATE);                    if(numread <= 0)             &

41、#160;             /下载完成通知安装                        mHandler.sendEmptyMessage(DOWN_OVER);    

42、60;                   break;                             

43、60;          fos.write(buf,0,numread);                while(!interceptFlag);/点击取消就停止下载.              

44、;                   fos.close();                is.close();           

45、  catch (MalformedURLException e)                 e.printStackTrace();             catch(IOException e)        

46、0;       e.printStackTrace();                                       &#

47、160;       /*     * 下载apk     * param url     */         private void downloadApk()        downLoadThread

48、 = new Thread(mdownApkRunnable);        downLoadThread.start();         /*     * 安装apk     * param url     */    private

49、 void installApk()        File apkfile = new File(saveFileName);        if (!apkfile.exists()             return;       

50、            Intent i = new Intent(Intent.ACTION_VIEW);        i.setDataAndType(Uri.parse("file:/" + apkfile.toString(), "application/vnd.android.package-archive"); &

51、#160;      mContext.startActivity(i);         第三步：在MainActivity.java也就是主Activity调用,代码如下:?12345678910111213141516171819package com.tutor.update; import android.app.Activity;import android.os.Bundle; public class Main

52、Acitivity extends Activity           private UpdateManager mUpdateManager;    Override    public void onCreate(Bundle savedInstanceState)         super.onCreate(savedInstanceState);        setContentView(R.layout.main);